Lithographic printing machine



Dec. 15, 1931.

A. J- `GRAF LITHOGRAHIC PRINTING MACHINE LITHOGRAPHIC PRINTING MACHIN E Filed Npv.`1e, 1929 2 sheets-sheet 2 n Y lNvsN-ron 'A ALBERT J. GRAF, 0F WmTFIELD, NEW JERSEY,v

fmtion andj the frame of c v the fountain roller' roller.

l contact with one Furthermore,

Patented pee.' 1s, 1931 I 4UNITED sTAras- PATENT omer.I

A SSIGNOR TO R.

roux, N.'Y., A conromrron or 'Naw rom:

LITHoGmnIc rmrme lacrima' l Application led November 16, 1929. Serial'lo. 407,711.

- This invention relates to lithographie printing machines in w 'ch moisture is applied to the printing plate byl a dampemng The mechanism for supplying-the moisture to the plate is commonly called a water moincludes a tray or 'fountain having a roller, rotatably supported so the lower side of its peripher is below the surface of the liquid in the fountain.

-A ductor roller is rotatably supported onl arms, whereby it may be swung alternately into contact with the fountain roller and into of a series of rollers that act totransfer the moisture from the ductor roller to the printing plate.

- In water motions heretofore used, the fountain was made of sheet brass and secured to the machine, in operative relation to a fountain roller that Awas also usual- It is difficult to support in proper alignment with without encroaching considerabl'y on the space available lforv cross members necessary for bracing the frame.

the brass roller rapidly becomes. coated with ink andwhat is underly made of brass. a fountain so made,

action, due to the presence of salts inthe solution used in the fountain, and certain ingredients in the ink which are carried back tothe fountain roller by the ductor roller. This coating causes the fountain roller to repel 'the solution, which interrupts thereonstant supply of moisture tothe printing plate, and thus causes poor printing.

In the fountain that is the subjectl ofthis invention, the tray that holds the solution, is preferably made of'cast iron formed integral vwith one of the cross braces that connect the side frames of the machine. The fountain roller is preferablymade of aluminum and is rotatably supported in bearings formed in' brackets secured tothe fountain member. It

has been found that this arrangement has the advantages of increased .strength, rigidity and accessibility, that no coating is formed ori-the fountain roller, and thus a better quality of printing is obtained. I It is; an objectl of the inventlon to provide resulting from chemical fountain thatis formed an improved water chlne.

non a co.,crI NEW Another object of the vinvention is to proi v1de a water fountainhaving a roller,'th e surface of which will remain clean and free from deposits that ordinarily form on the fountain rollerduring the operation of the machine.

Itis also an object of the invention to provide a ,water fountain of generally improved construction, whereby the device will be simple, durable and inexpensive in construction, as well as convenient, practical, service-y able and eflicient in its use.A

With the foregoing and other objects in view, which-will appear as the description proceeds, the invention resides in the combination'and arrangement of parts, and in the details of construction hereinafter described and claimed, it being understood that various changes in the precise embodiment of the invention herein disclosed may be made with-v in the scope of what is claimed without departing from the spirit of the invention.

he preferred embodiment of the invention is illustrated in the accompanying drawings, wherein:

F gure 1 is a diagrammatic view of a ortion of a lithographie printing mac ine showing the improved water fountain in sec.

tion, and thel eneral arrangement of coacti'ng parts of te machine, as they a pear on the line A-A of Figure 2, and mt e direction of the arrow; and Y Figure 2 shows a sectional longitudinal view of the fountain, itappears on the line in the direction of the -B of Figure 1, and arrow.

' l Referring to the drawings, 11 indicates a brace or cross member of the machine frame,

which serves wit other members to hold the partly broken away, as

side frames of the machine, not shown, in

proper alignment.

e water fountain, which is formed integral with the frame member, is Indicated at 12.

Brackets and 13', are secured t the frame member'll and are fitted with bear-v ings adapted torotatably support the founshown at 22, are also secured and support a d uctor-roller23. f-

It will be understood that rotationof the cam 17, results in moving the ductor roller 23, alternately into engagement .with the fountain roller 14 and the distributing roller 24.' The` fluid is thus ltransferred from the 15 fountainroller to the distributing roller 24, and from -it to the form rollers 25, by which the fluid is depositedon he plate carried by the cylinder 26.

v The dampening 2 the fountain by a circulating pump t a draws it from a reservoir and delivers it to the fountain at a rate considerably in excess yofthe requirements. .An overflow pipe 27,

' t keeps the fluid at the proper level and allows the excess to flow back into the reservoir.

The cock `.28, is provided in order that thek fountain may beL drained for cleaning..

\Grey castiron is a suitable material for the member that forms the combined foun- 39 tain and brace, and it is preferably galvanized to prevent corrosion; Aluminum is a suitable material for-the fountain roller, as

itsoxide does not repel water and as its sur- Ifaceis `kept wet, it does not take ink, furthermore, its place in the electro-chemical series makes it positive with respect to both the iron in thefountain and. the zinc with which the fountain isk galvanized.

fluid is usually supplied to tive to material in contact with the iiuid l the fountain. J I

5. Ina dampening mechanism for a lithographic printing mach-ine, a water fountain having a fountain .roller that is electro-posi- -tive to the metal of whichthe fountain isv made;

6. In a dampening mechanism for a lithographic printing machine, a galvanized water fountain integral with a frame member of the machine, an aluminum fountain roller, and bearing brackets secured to the frame member and adapted to rotatably support. the roller.

` 7. In a dampening mechanism for a lithographic printing machine, a water fountain formed-of a l tro-positive to the 8. In a d ampemng mechanism for a lithographic printing machine, a water'fountain sol ferrous material and havin a f fountain roller formed of a metal that is eicmaterial, .of which the. t fountain is formed.,

adapted to contain an electrolyte and having V a fountain roller electro-positive to the material of which the fountain is made, vand an electrical connection between the fountain roller and the fountain whereby an electric circuit is completed through the fountain roller, the electrolyte,

and the fountain. p In testimony whereof, I aiiix m si ature.

G nr.

. Acid. and alkaline ingredients'are usually 40 added to the water used 'in they form an electrolyte 1n contact with both d the .fountain roller. lAri the fountain an electric circuit is completed through the bearhtthat a in of the roller, and it is thoug the fountain and N5l slight electrolytic action results, lthat aids keeping the roller clean.

' What I claim is: g

1. Ii a dampening mechanism for a litho` graphic printing' machine, an aluminum.

fountain roller anda/water fountain formed` of a' lmetal that iis electro-negative to .the

2. In a dampening mechanism for `a lithographic printing machine, a galvanized iron water fountain 'and an aluminum fountain roller.'

3. In a d pening mechanism for a litho-r graphie printing machine, agalvanized wa- 00 terl fountain integral with -a frame member i of the machine, and an aluminum fountain u .rollen- 4.' In a'damp'enin-g mechanism for a litho- 'graphic printing machine, awater fountain 65 having afountain roller that is eltactrposiformed of a material that is iis 

